BLOCK 1457713 - Caterpillar

Illustration 3 g02631261
propel Pump (13) Electric displacement control (14) Displacement control spool (15) Reverse solenoid (16) Forward solenoid (17) Plunger (18) Line to pump case (19) Servo cylinder (20) Servo piston (21) Swashplate feedback linkage (22) Line to pump case (23) Line to case drain (24) Rotating group (25) Input shaft (26) Propel pump (27) Swashplate (28) Line to case drain (29) Multifunction valves (30) Servo relief valves (31) Line to case drain (32) Charge relief valve (33) Propel loop high-pressure line (34) Charge pump (35) Propel loop return pressure line (36) Combined suction and return filterPump input shaft (25) turns rotating group (24) and charge pump (34) when the engine is running. The rotating group contains the piston assemblies and cylinder barrel. The charge pump receives supply oil from combined suction and return filter (36). Charge oil flows through internal passages to charge relief valve (32), to multifunction valves (29), and to EDC (13). Forward solenoid (16) and reverse solenoid (15) are proportional solenoids. The machine ECM uses a pulse width modulated signal to energize the EDC solenoids. Energizing EDC solenoid causes plunger (17) to move. The distance that the EDC plunger moves is proportional to the signal from the machine ECM. When plunger (17) shifts, charge